0:01

This was an incidentally discovered

0:03

lesion in the parapharyngeal space.

0:06

The study was performed as a brain MRI for headaches,

0:10

and the brain examination looked pretty good.

0:13

However,

0:15

on the earliest image on the axial T2-weighted scan,

0:20

what was seen was a bright lesion in the deep portion

0:25

of the parotid gland versus the parapharyngeal space.

0:30

So, as you can see,

0:32

the normal parotid tissue extends in its deep portion

0:36

to become adjacent to the parapharyngeal space here.

0:42

This lesion was at that junction.

0:44

Now, as you can see,

0:46

this parotid gland deep lobe deep portion

0:51

starts to taper pretty rapidly here.

0:54

So this would be a little bit unusual for this to be

0:56

from the deep portion of the parotid gland with

0:58

a lobulated mass sort of pedunculated out.

1:02

So more likely,

1:03

this is located predominantly in the or

1:07

originates in the parapharyngeal space.

1:10

Let's look at the T1-weighted scan.

1:13

So in the T1-weighted scan,

1:14

we have a little bit more of assurance that this is

1:18

derived and arising in the parapharyngeal space fat.

1:23

Why do we say that?

1:24

Well, on the T1-weighted scan,

1:26

you can see bright signal intensity around

1:28

the periphery of this lesion here,

1:33

which corresponds to the parapharyngeal space

1:35

fat that you're seeing on the right side.

1:38

This appearance of the deep portion of the right parotid

1:42

gland looks very similar to that of the normal side.

1:48

So we would say that this is most likely arising in the

1:51

parapharyngeal space fat. The parapharyngeal space fat,

1:56

in addition to having fat,

1:57

often has residual or

2:02

implants of minor salivary gland tumor.

2:07

I'm sorry, minor salivary gland tissue.

2:10

So this is a not uncommon location

2:15

for minor salivary gland tumors.

2:19

And this was a pleomorphic adenoma

2:21

of the parapharyngeal space fat.

2:24

Let's look at the post gadolinium enhanced scan,

2:27

you can see that the lesion is well defined,

2:31

and this border of bright signal intensity

2:33

represents the parapharyngeal space fat.

2:36

And if we look at it on the coronal image as well,

2:40

we see the lesion here.

2:43

This is approached in general with a fine needle

2:46

aspiration right along this plane here,

2:49

through the face, through the fat in the buccal region,

2:56

and then through the masseter muscle

2:58

with a needle puncture. Here.

3:00

This is more advantageous than approaching

3:03

it through the parotid gland,

3:05

where you may have the potential for either paralyzing

3:09

temporarily with your anesthetic or

3:12

injuring the facial nerve. Here,

3:15

let's just show you on the Coronal T2-weighted image

3:21

how nice and lobulated it is.

3:23

It does have a sort of darker signal

3:25

intensity rim around it,

3:27

identifying it as most likely representing

3:30

a pleomorphic adenoma.